RIDGID R2740 Heavy Duty Variable Speed Belt Sander 3 in. x 18 in Twin Fan High Efficiency Dust Collection  while one fan cools the motor, the other collects dust resulting in maximum dust pickup efficiency Automatic Belt Tracking  tool automatically adjusts belt to center of platen for alignment Variable Speed Dial with Electronic Feedback  match the speed to the desired removal rate. Electronic feedback helps maintain motor speed under load for consistent results. Flush Sanding Capable  flat face allows for flush sanding against vertical surfaces Tool-Free Belt Release  makes changing belts quick and easy